#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
using namespace std;

const int N = 1e6 + 10, INF = 0x3f3f3f3f;

void solve()
{
    string a, b;
    cin >> b >> a;

    if (a == b) { cout << "Yes\n"; return; }
    if ((a == "Ocelot" && b == "Serval") || (a == "Serval" && b == "Lynx") || (a == "Ocelot" && b == "Lynx")) { cout << "Yes\n"; return; }
    cout << "No\n";
}

signed main()
{
    //ios::sync_with_stdio(0);
    //cin.tie(0);cout.tie(0);
#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
    std::istringstream in(R"()");
    std::cin.rdbuf(in.rdbuf());
#endif
    int T = 1;
    //cin>>T;
    for (int i = 1;i <= T;i++) {
        solve();
    }
}